This section of Darksiders 3 guide explains how to unlock attribute points. Attribute points are needed to increase Fury's statistics, making her more durable and her attacks dealing more damage.
A more obvious way of obtaining attribute points is to feed Vulgrim with souls. As a reminder, Vulgrim can be encountered next to fast travel portals.
Talk to Vulgrim, and choose the first dialogue option, which involves transferring gathered souls. After Vulgrim eats a certain number of souls you will get 1 attribute point. Vulgrim's appetite grows bigger and bigger - every next attribute point costs more than the previous one.
A less obvious way to get attribute points is to search for Luminous Visage artifacts. Luminous Visages are found in the same way as normal loot i.e. by gathering orange orbs.
Once found, you need to search your inventory for Luminous Visages (Crystals tab) and hold the button to crush it. Performing the aforementioned action unlocks an attribute point.